1. Field of the Invention
Exemplary embodiments of the present invention relate to a display substrate, a method of manufacturing the display substrate and a display panel having the display substrate. More particularly, exemplary embodiments of the present invention relate to a display substrate applicable to transmissive and reflective-type liquid crystal display (“LCD”) device, a method of manufacturing the display substrate and a display panel having the display substrate.
2. Description of the Related Art
Liquid crystal display (“LCD”) devices may be classified into transmissive-type LCD devices, reflective-type LCD devices and transflective-type LCD devices in accordance with light sources. Since a transmissive-type LCD device has relatively high visibility and color reproducibility in an indoor environment, it is widely used. However, the transmissive-type LCD device has relatively low visibility in an outdoor environment, and power consumption thereof is high.
In contrast, a reflective-type LCD device has relatively high visibility in an outdoor environment. However, the visibility thereof is remarkably reduced in a dark place or cloudy weather.
Accordingly, a transflective-type LCD device has been developed, which has advantages of both the transmissive-type LCD device and the reflective-type LCD device. However, the transflective-type LCD device is more disadvantageous in terms of optical structure or manufacturing process than the transmissive-type LCD device and the reflective-type LCD device. For example, in the transflective-type LCD device, the number of light paths passing through a liquid crystal layer corresponding to a transmissive area is one, while the number of light paths passing through a liquid crystal layer corresponding to a reflective area is two. That is, incident light incident into the reflective area passes through the liquid crystal layer, and then the incident light is reflected by a reflective electrode to again pass through the liquid crystal layer, so that the number of light paths is two in the reflective area. Thus, a phase delay difference is undesirably generated between the transmissive area and the reflective area.
To solve the disadvantages, the transflective-type LCD device employs a dual cell gap structure in which the thickness of an organic insulation layer is controlled, so that a cell gap of a liquid crystal layer corresponding to the transmissive area is double that of a cell gap of a liquid crystal layer corresponding to the reflective area. However, a manufacturing process of the transflective-type LCD device is relatively complicated due to a process of controlling the width of the organic insulation layer. Thus, the productivity of the transflective-type LCD may be undesirably reduced.
In addition, in the transflective-type LCD device, a surface of the organic insulation layer is embossed to improve the reflection efficiency of the reflective area, and then a reflective electrode is formed on a final layer. Thus, two photolithography processes are added with respect to a manufacturing process of the transmissive-type LCD device, so that a manufacturing process of the transflective-type LCD device may be undesirably complicated.